Low-wetting electrostatic application device and associated method

ABSTRACT

An electrostatic device that includes: an air flow regulator system including a pressure regulator and an air flow regulator; a liquid flow regulating system including a set of restrictors; an electrostatic system including an electrostatic emission antenna and an insulating hood of the electrostatic emission antenna; an air-liquid nozzle that is separated from the electrostatic emission antenna; a tank; a positive displacement pump and a low-wetting electrostatic application method.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. national stage patent application ofInternational Patent Application No. PCT/CL2019/050008, filed on Feb. 1,2019, which claims priority of CL 0341-2018, filed on Feb. 6, 2018, theentire contents of each of which are incorporated herein by reference.

FIELD OF THE DISCLOSURE

The invention relates to a device comprising an electrostaticapplication system that operates with ultra-low volume and allows theapplication of liquid or gaseous products, or mixtures thereof, for thepost-harvest treatment of fruits or vegetables before packaging, in theprocess lines of packing facilities or orchards. The device deliversdrops of a few microns in diameter and the adherence of themicrodroplets is achieved through the application of an electrostaticcharge, achieving optimum coverage of the product applied to the treatedsurface. The electrostatic device that allows the control of the amountof product applied, allows to decrease the amount of product used,reaching a low wetting “dry effect” application. In addition, the deviceallows working at different ambient temperatures, delivering preciseamounts of the applied product, which is deposited by loading effect onthe surfaces treated in a very homogeneous way.

The invention also relates to a dry effect application method, that is,the treated surface does not show evidence of the application within afew seconds of the electrostatic application because of the small sizeof the microdroplets applied and the homogeneity of the application as aresult of the electric charge that is induced to each one of themicrodroplets, avoiding the superposition of the same and thus theaccumulation of product in a specific point. Not adding water on thetreated surface decreases the incidence of fungus growth since humidityis one of the vectors that influence their growth and the probability offungal attack decreases when humidity is not present. In addition, ananti-dehydrating protective agent may be deposited during theapplication.

BACKGROUND OF THE DISCLOSURE

During the storage and transportation of fruits or vegetables forexport, decomposition and dehydration generate enormous economic losses.Fruit or vegetable exporters are looking for alternatives to storetreated products in good condition for periods of more than 30 days inorder to avoid such economic losses.

Various devices for the application of chemical or phytosanitary agentsto the harvested fruit can be found in the prior art to prevent diseasein the fruit. The amount of chemicals used to wet the fruit is excessiveand requires it to be subsequently placed in drying chambers.

WO 2007009474 discloses an application method of phytosanitary productsonto post-harvest fruit under controlled conditions by electrostaticspraying. However, the method requires a hood that collects excess spraysolution that has not settled on the fruit.

EP 2620728, U.S. Pat. Nos. 8,191,805 and 8,317,113 relate toelectrostatic devices for controlling ambient humidity by freezing itand subsequently melting the water in the atomizing device by means of aheat transfer device.

U.S. Pat. No. 4,971,818 relates to a method for spraying a harvestedcrop using a rotary-type electrostatic sprayer comprising: moving thecrop along a conveying line, surrounding and covering a region of saidbelt with electrodes formed by lead wires from 100 to 150 meters thatextend rolled in thirty turns that cover the application area of thespraying device.

The application system of equipment operating in chambers at atemperature below 0° C. encounter a problem, specifically in the nozzlethrough which the product exits. The reason is that the liquid thatpasses through the nozzle freezes when exposed to the compressed airthat atomizes it, whose temperature is 2 degrees (−2 degrees) lower whenthe air expands, clogging up the nozzle and preventing the application.The nozzle clogs up when frozen and prevents the passage of liquid.

In the prior art, the most commonly used technique to prevent thedevelopment of diseases in the fruit for export is the use of SO₂generators, which includes a stage of rapid release of SO₂ and a stageof slow release of SO₂, within each of the boxes containing the fruitduring the packaging and transport process.

SUMMARY OF THE DISCLOSURE

In some embodiments, the devices and methods described herein makes itpossible to keep fruit or vegetable for export in good condition for aperiod of 45 to 90 days or more, avoiding the development of diseasesand reducing their dehydration during the storage and transportationperiod, allowing exporters to plan exports with a broader time frame,and thus obtain greater commercial profitability.

In some embodiments, application of an ultra-low volume of the solutionavoids having to collect an excess thereof and, in turn, to treat thecontaminating residues described in the prior art.

In some embodiments, moisture or wetting the treated surface of thefruits or vegetables may be avoided in order to keep them in goodcondition during storage and transport.

In some embodiments, the device includes an electrode with a simplifiedstructure, easy to install at the packing site and which manages tocontrol the amount of product applied and allows it to work at differentambient temperatures.

To solve the problem of a nozzle clogging up when frozen and preventingthe passage of liquid, in some embodiments, a device for post-harvesttreatment that allows working at different temperatures, includingtemperatures below 0 degrees Celsius. To achieve application at lowtemperatures, the device includes a heating element for the nozzle. Thisheating element allows the nozzle to be kept at a temperature higherthan room temperature, preventing the product passing through it fromfreezing and clogging it. The device also comprises a tank heatingsystem in which the product to be applied is stored, which prevents theproduct to be applied from freezing when passing through the tubes orhoses before reaching the nozzle.

In some embodiments, a device for post-harvest treatment beforepackaging, which comprises a flow control system for the liquid and/orgaseous products that are applied. It allows the application of preciseamounts of liquids of different densities and of different pHs, andallows to work at an application temperature ranging from −5 degrees to50 degrees Celsius, thus maintaining a constant application flow.

In some of the embodiments, the device allows the application of liquidand/or gaseous products after harvest and, specifically, allows theapplication of an ultra-low volume of different chemical, organic orecological products to meet different production standards in chambersthat operate at low temperatures. It also allows regulating andcontrolling the amount of product applied without wetting the treatedsurface, achieving a dry effect and avoiding the application of excesswater. This makes it possible to avoid the humidity that is thefavorable environment for growth and development of fungi andundesirable microorganisms. In some embodiments, the device achieves adry effect, that is, it has a minimum wetting capacity in the range from0.3 cm³ to 10 cm³ per square meter, so that the surface treated by thedevice of the invention is surprisingly dry within a few seconds of theapplication, and this avoids an additional drying step of the treatedsurface.

In some embodiments, the device makes it possible to deliver ahomogeneous application of the product that can even reach the surfaceof the fruits or vegetables at the bottom of a box or container. Inaddition, it allows the applied product to adhere to the surface of thefruits or vegetables in hard-to-reach places such as, for example, thepoints of inflorescence and even the fruit stalks that other devices areunable to cover.

In some embodiments, the electrostatic device may be versatile in thatit allows the application of different products. For example, in someembodiments, the electrostatic device may be adapted for the applicationof gases, such as ozone, to sanitize the packing site.

In some embodiments, the device may also be used to apply fungicides ordisinfectants to the packaging materials of the fruit, such as cardboardor plastic boxes, or the paper used to separate the fruits inside a box.

For example, it is possible to apply products to blueberries packed inPunnets or Clamshells. This is because the critical point of rot iswhere the fruit is in contact with the container. A fruit is woundedwhere there is a point of friction, but if the container is sanitizedwith a fungicide coating, the possibility of rot decreases. According tosome embodiments, this is made possible with the device because itallows a dry effect application, that is, with a minimum application ofwater, so that the properties of the materials on which the product isapplied are not altered since it does not add excess water to thesurface.

In addition, the device allows the application of mixtures of productsthat include covers to the surface of fruits or vegetables. The coversallow maintaining the organoleptic characteristics and avoid dehydrationor weight loss during storage or transport. For example, it allows theapplication of wax to apples, the application of organic products tomeet industry standards, the application of edible toppings, beeswax,synthetic waxes, sugars, cinnamon or propolis extract.

In some embodiments, the application system of the device allows todetermine precisely the amount of product to be applied per applicationarea and surface treated.

The invention will be described in detail below, with reference to theaccompanying drawings, which illustrate embodiments of the invention.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a schematic representation of the electrostatic device,according to some embodiments.

FIG. 2 shows a schematic representation of the liquid flow regulationsystem.

FIG. 3 shows the application system with each of its componentscomprising the nozzle and the heater.

FIG. 4 shows a view of the application system.

FIG. 5 shows an elevation view of the insulating hood.

FIG. 6 shows a cross section of the insulating hood.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

In some embodiments, an electrostatic device comprising: an air flowregulator system including a pressure regulator (12) and an air flowregulator (13); a liquid flow regulating system (35) comprising a set ofrestrictors (26); an electrostatic system comprising an electrostaticemission antenna (7) and an insulating hood (9) for the electrostaticemission antenna; an air-liquid nozzle (6) that is separated from theelectrostatic emission antenna (7); a tank (5); and a positivedisplacement pump (4).

In some embodiments, the electrostatic device for post-harvest treatmentcomprises an electrostatic emission antenna, an insulating hood, a flowrate control system or liquid flow regulator (through nozzles or flowrestrictors), a pressure regulator, an air flow regulator, a positivedisplacement booster pump, a pond, an air-liquid nozzle. Likewise, thedevice includes a temperature control system (of the tank and nozzle) towork in different environments and at different temperatures, whereinthe equipment is adapted to work at low temperatures in chambers thatoperate at temperatures below 0° C. or even −2° C.

In some embodiments, an electrostatic application method comprises:

-   -   providing an air flow to an insulating hood (9) of an        electrostatic emission antenna (7) and to an air-liquid nozzle        (6) that is separated from the electrostatic emission antenna        (7);    -   providing a liquid flow from a tank (5) to the air-liquid nozzle        (6) by means of a positive displacement pump (4);    -   regulating the air flow by means of a pressure regulator (12)        and an air flow regulator (13);    -   regulating the liquid flow (35) that passes through a set of        restrictors (26); and    -   turning on the power directed to the electrostatic emission        antenna (7).

Control Console

The equipment comprises a control console (2) that allows centralcontrol of the equipment. The console comprises an on/off control, anelectrostatic generator system control, a pump power source control, acontrol for remote or manual control, and may further comprise a controlof the air flow regulators at the nozzle and a liquid flow regulatorcontrol.

The control console includes a power light that indicates that theequipment is connected to the electrical network; an on/off switch thatturns the equipment on or off; a remote control or manual control switchthat activates the use of the command console or the use of the remotecontrol (3); a pump switch that activates the pump (4) allowing thearrival of liquid from the tank (5) to the application nozzle (6); anelectrostatic switch that activates the electrostatic power directed tothe electrostatic emission antenna (7); it may also comprise a switchthat activates the power directed to the nozzle heater and the tankheater.

A high voltage power line (8) comes from the control console (2), goesto the electrostatic emission antenna (7) and passes through the hood(9) before reaching the electrostatic emission antenna. The hood (9)fulfills the function of isolating the high voltage power line (between5,000 to more than 30,000 volts) by means of an air flow that surroundsthe high voltage power line going from the hood to the electrostaticemission antenna.

A power line (10) also comes from the control console (2) and isdirected to the heater (11) of the nozzle (6). See FIG. 1.

Air Flow Regulator

According to some embodiments, to regulate the air flow coming out ofthe nozzle, the equipment comprises an air flow regulator system thatincludes a pressure regulator (12) and an air flow regulator (13). Theair flow regulator (13) comprises a flow rate meter that comprises asmall steel ball in a graduated column, where the steel ball is pushedby the air flow.

Compressed air is supplied by a compressor (15). An air line (16) exitsfrom the compressor and branches into two air lines: a first air line(17) that carries air to the nozzle, and a second air line (18) thatcarries air from the electrostatic emission antenna (7) to theinsulating hood (9). See FIG. 1.

According to some embodiments, it is important that the compressed airgoing to the insulating hood be dry air, so that the air keeps an areaof the hood dry in order to isolate the high voltage power line (from5,000 to more than 30,000 volts) directed to the electrostatic emissionantenna, in order to avoid electrical conduction between theelectrostatic emission system and the other elements of the device, andthus avoid the formation of an electric arc and burning the high-voltagepower cables. In the absence of this dry air flow coming out of thehood, the same product that is applied by the nozzle would contaminatethe hood, generating a conductive bridge between the electrostaticantenna and the structure of the equipment that is connected to groundfor electrical protection.

The first air line (17) that carries air to the nozzle passes throughthe control console (2) where it meets a pressure regulator (12) and anair flow regulator (13), which allows the air flow to be regulated goingto the nozzle. The second air line (18) that carries air to theinsulating hood (9) has a restrictor (19) that controls the amount ofair that goes to the insulating hood. See FIG. 1.

According to some embodiments, the device comprises a pressure regulator(12) that allows to regulate the droplet size indirectly by controllingthe air pressure. The air pressure can be varied, for example, between 1to 2 bar (100 to 200 KPa) to control the size of the droplet that exitsfrom the nozzle.

By regulating the air flow, the droplet size can be regulated, where thedroplet size is inversely proportional to the applied air flow. Ingeneral, an air flow can be measured by pressure difference, whereby anair flow can be approximately calculated. However, according to someembodiments, device comprises a gas flowmeter that directly measures theflow. In some embodiments, directly measuring the air flow is importantin the device because the droplet size is controlled by the air flow.The droplet size required in the application depends on the ambienttemperature. At a higher ambient temperature, a larger droplet sizeshould be used in order to prevent the droplet from evaporating beforereaching the surface to be treated, that is, on the way from the nozzleto the target surface. The path can be, for example, betweenapproximately 20 cm to 200 cm.

Furthermore, in some embodiments, a flowmeter may be implemented in thedevice to regulate the air flow directed to the nozzle. By regulatingthe air flow directed to the nozzle, the droplet size can be regulatedmore precisely. The flowmeter regulates the air flow from 0 to 25 litersof air per minute on the principle that the greater the air flow, thesmaller the droplet size.

In addition, controlling the droplet size that depends on the amount ofair going to the nozzle allows regulating the amount of product to beapplied.

For example, when 1 bar (100 KPa) of pressure is applied, the dropletsize is very large and the treated fruit remains wet a few seconds afterthe application. The pressure is then increased, which increases the airflow rate, thereby reducing the droplet size and increasing the liquidflow rate, which increases the liquid flow that passes through therestrictors across the binary control system or decreases the amount ofreturn to the tank to maintain the liquid flow rate at this new airflow.

Flow Rate Control and Liquid Flow Regulator

The electronic flow rate meters of the state of the art are not suitablefor measuring low flows in the equipment of the invention, so a massflowmeter was sought.

In some embodiments, the electrostatic device comprises a flowregulating system for the liquid products that are applied. The flowregulator system allows the use of liquid products of differentdensities, different pHs, or a mixture of products, and allows workingat temperatures from −5 to 50 degrees Celsius, maintaining a constantflow of product that exits from the nozzle.

Flow regulators in the prior art had problems working at temperaturesbelow 5° C. A flow regulating system (35) had to be implemented in thedevice, which is shown in FIG. 2.

In some embodiments, the liquid flow regulating system (35) comprisesthe use of in-line nozzles or a set of restrictors (26), a binary switchsystem (40) that allows opening or closing the restrictors (31, 32, 33,34) through solenoid valves (41), and a return flow measurement systemcomprising a regulating valve (36), a flow control (37) and a flowmeter(38). So that the flow regulating system (35) regulates the flow rateand allows to deliver predetermined and measured quantities of productthrough the nozzle of the device, according to some embodiments.

The flow regulating system (35) of FIG. 2 shows that the liquid exitsthe tank (5) through a first liquid line (22) and passes through afilter (29). The liquid is driven by the positive displacement pump (4)to a fork (21), where it separates into: a second liquid line (23) and areturn liquid line (24). The second liquid line (23) comprises a linefilter (25) and a set of restrictors (26) that regulate the amount ofliquid that goes to the nozzle. The return liquid line (24) is returnedto the tank. The return line (24) comprises a regulating valve (36), aflow control (37) and a flowmeter (38) that measures the liquid flowthat is returned to the tank (5). In the return liquid line (24) theliquid flow is much higher, approximately 2 liters per minute, whichallows the amount of return liquid to be measured accurately and, at thesame time, allows the contents of the tank to be stirred with the liquidreturning to the tank.

After passing through the set of restrictors (26), the second liquidline (23) encounters a first check valve (27) that prevents the liquidfrom returning to the restrictors so that the liquid flow that it isdirected to the nozzle through the third liquid line (30) is maintainedmeasured and constant.

The device comprises a line filter (25) that goes from the fork (21) tothe set of restrictors (26) prevents the restrictors from being cloggedup in the second liquid line. The device also comprises a second checkvalve (28) that is located just before the nozzle (6) to prevent liquidfrom returning from the nozzle.

The flow regulating system (35) comprises a set of restrictors (26)comprising restrictors (31, 32, 33, 34) of different thickness. Therestrictors (31, 32, 33, 34) are located in the second line of liquidthat goes from the pump to the application system. The restrictors (31,32, 33, 34) have different internal diameters ranging from approximately0.3 mm to 1 mm in diameter.

For example, the set of restrictors (26) comprises a 1XF restrictor (31)(a given unit flow), a second 2XF restrictor (32) (twice a given flow),a third 4XF restrictor (33) (four times a given flow), a fourth 8XFrestrictor (34) (eight times a given flow). The amount of liquid thatgoes to the spray nozzle (6) can be regulated with the opening andclosing of the restrictors (31, 32, 33, 34) through the solenoid valves(41) by means of a binary system.

In one embodiment of the device, the return flow measurement system inthe flow regulating system (35) can be replaced by a set of returnrestrictors with a larger internal diameter ranging from approximately 1mm to 5 mm in diameter. Therefore, the amount of return liquid could beregulated manually by changing the diameter of a return restrictor orwith a set of larger diameter return restrictors that could beinterchanged in order to regulate the liquid that is returned to thetank through the return line (24). In this embodiment, the devicecomprises a set of flow restrictors that are interchangeable and areused depending on the amount of product to be applied. For example,there could be a set of 8 restrictors, 4 application restrictors, and 4return restrictors. Restrictors can be interchanged to achieve theproper flow of application.

In some embodiments, the liquid flow regulating system (35) allowsregulating the flow more precisely, avoiding the manual exchange ofrestrictor in the device. This prevents having to stop the operation ofthe equipment and the conveying line in order to rig the device to carryout an exchange of restrictors and recalibrate the equipment.

In some embodiments, the flow regulating system allows flow ratecontrol, for example, from 0 to 250 cm³/min, from 0 to 150 cm³/min, from0 to 50 cm³/min, preferably from 10 to 20 cm³/min, more preferably 15cm³/min.

Nozzle

FIG. 3 shows the application system of the electrostatic device,comprising an air-liquid spray nozzle (6), according to someembodiments. The nozzle (6) is made of stainless steel, with a flat fan,which allows to generate droplets of variable size. The air-liquidnozzle allows the atomization of the product to be applied. The nozzlecomprises a liquid inlet (49) that receives the liquid that comes fromthe third liquid line (30) and an air inlet (50) that receives the airthat comes from the first air line (17).

The nozzle (6) is attached to a flat surface (75) located at the lowerend of a nozzle holding tube (42). The nozzle is housed in the spaceformed between a nozzle holder (43) and the flat surface (75). Thenozzle holder (43) forms a rectangular frame with an open end, the openend comprises fastening tabs (76) that include threaded holes into whichbolts (45) are screwed to secure a nozzle cap (44). The nozzle cap (44)has a flat shape and has two perpendicular surfaces that comprise arecess (73) so that it can be inserted into an anchoring slit (74)located at the rear of the lower end of the nozzle holding tube (42).

The nozzle holder (43) houses a nozzle heater (11) which is supported bya heater cover (47). The heater cover (47) is made of heat conductivematerial, has a flat shape and has two perpendicular surfaces that havean anchoring protrusion (71). The anchoring protrusion (71) is insertedinto an anchor hole (72) of the nozzle holder (43) to hold the nozzleheater in place. The nozzle holder (43) has a power line hole (48) forthe entry of the power line to the heater.

An anchor plate (46) closes the rectangular frame of the nozzle holder(43) by means of bolts (45) that are inserted into holes located at theends of the anchor plate (46). The holes in the anchor plate (46) matchthe threaded holes located in the holding tabs (76) of the nozzle holder(43). The bolts pass through the holes in the anchor plate (46) and pushthe nozzle cap (44) which is inserted into the slots (74) to hold thenozzle and heater in place. See FIG. 3.

FIG. 4 shows the assembled application system where the nozzle heater isclosely fitted to the heater cover (47), which, in turn, is closelyfitted to a flat surface of the nozzle, so that the heater is in contactwith the nozzle cap and nozzle surfaces and the heater can heat thenozzle by contact.

Temperature Effect

The temperature control system allows to work independently of theambient temperature, and allows the device to become independent fromthe properties of the product or composition applied and from theenvironmental conditions of the treatment site.

When working in refrigerated environments, the liquid can freeze in thenozzle which clogs up the lines and renders the nozzle inoperable. Toavoid this problem, a heating system was chosen using a nozzle heaterand a tank heater that can start operating when the ambient temperaturerequires it.

In some embodiments, the present invention comprises a heater at thenozzle (11) due to the need to work at temperatures below 2° C. or closeto 0° C. or below zero, such as −5° C. At low temperature, the productthat is applied can freeze when exposed to the compressed air thatatomizes it, whose temperature is less than 2 degrees, (−2 degrees) whenthe air expands, sealing the nozzle causing the nozzle to clog up andpreventing an application.

When the volume to be applied is low, that is, between 5 to 15 cm³ perminute, a nozzle heater is required. If the application volume isgreater, for example, from 20 to 160 cm³ per minute, then a heater forthe tank where the liquid to be applied is kept is also required.

The heating element of the nozzle comprises an electric resistance, forexample, equipped with two electric resistors of 5 watts each. Theheating element comprises a heater cover (47), an electrical resistanceand a heater power line (10) electrically connected to the electricalresistance located inside the heater cover (47).

Voltage

The problem of applying more than 1,200 volts, for example, arisesbecause the applied product is a conductive product comprising, forexample, water, salts and an active product, and can generate an arc.The arc can produce a spark that can lead to the burning of the hosesthat carry the product to the nozzle. When an arc occurs, the effect ofthe electrostatic field is nullified, causing the charged particles thatare applied to the target surface to separate.

Some devices of the prior art that work at approximately 1,000 volts,for example, do not allow application more than 30 cm away from thesurface to be treated because a recharge of the particles occurs, thatis, the particles lose the charge effect. As a result, the electrostaticeffect is lost and the atomized particles lose the ability to adhere tothe surface.

The device applies a voltage greater than 15,000 volts. For example, thedevice for the treatment of cherries uses approximately 15,000 volts andthe device for blueberries operates at approximately 30,000 volts, whichis much higher than the voltage applied by most of the equipmentdescribed in the prior art.

Electrostatic devices in which the electrostatic emission component is acomponent of the nozzle are also described in the prior art. Instead, inthe device, electrostatic stimulation is applied remotely from thenozzle, according to some embodiments.

In some embodiments, the device comprises a nozzle (6) that isindependent and is separated from the emission antenna that generatesthe electrostatic field. For example, the nozzle (6) and theelectrostatic emission antenna (7) can be at a distance of between 5 to30 cm from each other.

If a higher voltage is applied, the number of charged particlesincreases. The device charges both liquid particles and air particlesthat come out of the nozzle.

As the applied voltage increases, the number of charged particlesincreases and the charge of the particles increases, thus increasing theapplication distance and increasing the coverage of the treated surfaceto achieve a long-range electrostatic system.

In some embodiments, the device allows to apply even inorganic productssuch as copper or silicon that are highly conductive, because the devicehas an insulating hood (6).

Furthermore, according to some embodiments, the device makes it possibleto avoid the electric arc by regulating the distance between theelectrostatic emission antenna and the atomization nozzle (6). Thisallows to apply highly conductive inorganic products and avoid electricarc, by increasing the distance between the high voltage electrostaticemission antenna and the nozzle (6).

Furthermore, in some embodiments, the device comprises two ground cables(51). A ground cable runs from the nozzle holder to the control console(2). A second ground cable runs from the tank (5) to the control console(2). See FIG. 1.

Tank

In some embodiments, the device further comprises a tank (5) containingthe liquid to be applied, which has a pumping system and a temperaturecontrol system.

The tank, made of stainless steel, has from 5 to 60 liters capacity,preferably from 10 to 50 liters capacity, for example, 15 or 13 literscapacity, and comprises a stirring system. The stirring system comprisesthree pumps arranged at the base of the tank. The tank also includes atemperature control system that allows the product to be kept at asuitable temperature to prevent the liquid from freezing in the hoseswhen the ambient temperature is below 0° C.

The tank may be made of PVC, however stainless steel is more preferable.The size of the tank depends on the amount of product to apply. Smallertanks are often used with more concentrated products so that they alsorequire stirring to maintain a homogeneous concentration of the liquidinside the tank.

It is important to keep stirring the contents of the tank. For example,a 10-liter tank is also stirred by the movement of the liquid thatreturns to the tank. A 60 liter tank, for example, requires stirring by3 pumps located symmetrically at 120 degrees at the base of the tank.Additional stirring occurs by suctioning the center of the tank to theperiphery to prevent the product from decanting inside the tank.

Pumping System

The equipment includes a pumping system that includes an acid-proofpositive displacement pump (4) that drives the product to be applied tothe nozzle (6), returning 90% of its flow to the tank to keep theproduct stirred and homogeneous.

Pump

The positive displacement pump (4) drives the liquid from the bottom ofthe tank (5) to the nozzle (6). The pump is activated from the controlconsole (2) and can be powered by an electric motor. The booster pumphas a 12-volt electrical connection that connects it to the controlconsole.

The booster pump also pumps liquid to the top of the tank through areturn line (24). The return line (24) generates circulation of theliquid inside the tank. The first liquid line (22) that comes from thetank (5) passes through a filter (29) that prevents the pump frombecoming contaminated or clogged.

In some embodiments, the pumps used by the device are diaphragm pumps;gear pumps can also be used. The use of diaphragm pumps is preferredbecause gear pumps often leak.

According to some embodiments, the diaphragm pump (4) is a positivedisplacement pump, operating at up to 70 pounds of pressure, preferablybetween 20 to 40 pounds of pressure. The pressure increase is carriedout by the push of elastic membranes or diaphragms, which allow thevolume of the chamber to be increased or decreased by controlling themovement of the fluid from the area of lesser pressure to the area ofhigher pressure.

In some embodiments, the diaphragm pump (4) offers certain advantagesover other types of pumps, since they do not have mechanical seals orgaskets that are the main causes of breakdown of pumping equipment insevere conditions. Maintenance of the pump is quick and easy and haseasy-to-replace components. The diaphragm pump allows working atdifferent temperatures, is resistant to corrosion and is widely used inthe industry for the movement of practically any liquid.

The pumps stir the product and allow the liquid coming from the tankfrom a first liquid line (22) to rise to the nozzle (6). The hoses thatcome out of the pump (4) branch to form a return liquid line (24) thatgoes from the pump to the tank (5) and another hose to form a secondliquid line (23) that goes from the pump to the application nozzle (6).

The equipment also includes regulating valves. The function of theregulating valves is to keep constant the flow of air and liquid that issupplied to the air-liquid nozzle. The user controls the regulationdepending on the amount of product that needs to be applied to thetarget surface.

Electrostatic System

The electrostatic system comprises an electrostatic emission antenna(7), a protective and insulating hood (9), a tube for the high-voltageconductor element (56) that carries the high voltage power line (8) andsupports that secure the tube of the high voltage conductor element (56)to a horizontal part of the nozzle holding tube (42).

The electrostatic emission antenna (7) is responsible for generating theelectrostatic field that allows the separation of the particles of theproduct that is applied to the target surface. The electrostaticemission antenna (7) is activated from the control console. Theinsulating hood (9) prevents the formation of electric arcs to thedevice structure.

Hood

In some embodiments, the electrostatic device comprises an antenna thatgenerates an electrostatic field, which is located at the bottom of ahood (9). The hood (9) isolates the electrostatic emission antenna (7)from the rest of the components of the device.

The hood (9) is shown in FIG. 5. The hood (9) comprises an internal tube(52) and an external tube (53), an upper hole (54) for the entry of thehigh voltage conductive element (56) and a lower lateral hole (55) forthe entry of dry air (57) that acts as an insulator. The high voltageconductive element (56) enters through the upper hole (54) and exitsthrough a lower hole (61) of the internal tube (52).

The internal tube (52) allows the cable of the high-voltage conductorelement (56) that goes to the electrostatic emission antenna (7) to comeout in a position equidistant from the outer wall (63) of the externaltube (53) of the hood. Maintaining a distance between the electrostaticemission antenna (7) and the lower edge of the outer surface of theexternal tube (53) of the hood is critical to avoid the formation of anelectric arc. When working at more than 15,000 volts, it is sometimesnecessary to increase the distance between the electrostatic emissionantenna (7) and the lower edge of the outer surface of the external tube(53). If necessary, the distance between the electrostatic emissionantenna (7) and the hood may be increased, for example, by lengtheningthe cable of the high-voltage conductor element (56), or by using a hoodwith the external tube (53) having a larger diameter.

The hood (9) comprises a lower lateral hole (55) through which enters ahose that injects dry air (57) in the form of an air jet between anexternal tube (53) and an internal tube (52) of the hood (9). The airjet forms an air chamber that keeps the area formed between the externaltube (53) and the internal tube (52) dry. The air jet dries the outersurface of the inner tube (58), that is, the air jet dries the areaformed around the central space through which the high-voltageconductive element (56), that goes to the electrostatic emission antenna(7), exits. The air prevents the surface around the space from where thehigh-voltage conductive element (56) exits from getting wet and preventsthe formation of an electric arc that produces a spark, so that the airchamber formed in the area between the external tube (53) and theinternal tube (52) prevents the effect of the electrostatic field of thedevice, which separates the particles, from being nullified by theaction of an electric spark or a flame.

FIG. 6 shows a cross-section of the hood (9) comprising an upper tube(59) that has an upper hole (54) through which the high voltage powerline (8) enters. The high voltage power line (8) that carries the highvoltage conductive element (56) passes inside the internal tube (52),exits through the lower hole (61) and goes to the electrostatic emissionantenna (7). The diameter of the upper tube (59) of the hood is greaterin the middle part (60) to form a truncated hollow double-wall conehaving a lower wall (62) and an outer wall (63). The outer wall (63)forms the external tube (53) and comprises a lower lateral hole (55)through which the second air line (18) enters, bringing dry air (57) tothe space formed between the inner wall (62) and the outer wall (63).The dry air (57) forms an air chamber (64) by injecting a jet of dry airthat comes from the second air line (18) that enters through the lowerlateral hole (55) of the hood (9).

The hood is made of machinable, non-conductive plastic materialresistant to acidic chemical. The material must be of high wearresistance and high abrasion resistance. The hood material may be ofultra-high molecular weight and high-density polyethylene, such asRobalon. Alternatively, the material of the hood can be Teflon orTechnyl. Technyl is a polyamide with thermoplastic characteristics thathas good resistance to chemical agents and is easy to machine, has greatmechanical resistance, and excellent wear resistance.

In some embodiments, the device further comprises other optionalcomponents including a remote control, an aluminum mounting stand thatallows mounting on all types of process lines, a general holding tripodand a dome.

Remote Control

In some embodiments, equipment also includes a remote control (3) thatincludes a system for remotely starting and stopping the equipment toautomate the application. The remote control (3) is connected to thecontrol console (3) or may be wireless.

The remote control allows starting or stopping the application from morethan 15 meters away. In order for the remote control to be activated,the “Remote Control” switch must be selected in the control console.When the “Remote Control” switch is on, the remote control replaces theoperation of the switches of the pump and electrostatic system in thecontrol box.

Stand

In some embodiments, the device can be installed in any part of thepacking line on a stand (65) that is very little invasive. in its lowerpart. The lower part of the stand is a tripod comprising a foldingfastening element (70) and a main column (67) provided with anattachment (68) that allows adjusting the height of the main column(67). The main column (67) also includes clamps (69) that allow tosecure the tank, the filter and the pump to the stand. Furthermore,according to some embodiments, the device allows the position of thenozzle (6) and the electrostatic system to be regulated by means of aregulator (66) that allows the length of the horizontal part of thenozzle holding tube (42) to be adjusted. Adjusting the length of thehorizontal part of the nozzle holding tube (42) is important because thenozzle must be at half the width of the packing area to achieve auniform application.

The device can be automatically synchronized with the packaging line sothat if the packaging line stops, the device stops working to avoidover-wetting of the application area.

Dome

A dome can be used to protect the application area of the product. Thedome prevents drafts produced in the packing area, often by internalfans, from interfering with the application of the products to thetreated surfaces.

The dome may be installed at the application site to avoid “drift”,which is the movement of the particles away from their target, that is,to avoid all those applications that do not reach the target surface andthat constitute a loss of product, and can generate undesired effects inthe environment around or near the application site. Drift can occurduring application, especially when spraying small-sized dropletselectrostatically charged with volatile product, or when an air currentis generated in the packing area.

Drift can also occur at the lower edges of the dome. To avoid drift, anair curtain may be applied to the lower edge of the dome. To this end,the device may optionally include an additional pressure regulator (14)that controls the air flow applied to a tube provided with holes thatform an air curtain at the bottom of the dome and prevents productdroplets from escaping from the application site.

Calculation of the Dose to Apply

According to some embodiments, to calculate the amount of product ormixture to be applied with the device, it must be determined how muchproduct or mixture must be added to 1 liter of water to obtain therecommended dose for application to the fruit.

The packing lines operate at a constant speed, so that a place on theline is selected to install the device.

The width A of the packing line is measured, a length L is determined todefine the application area and the time T in seconds that the fruittakes to travel the distance L is calculated. Therefore, the speed ofline V_(L) is equal to L/T.

V_(A) is the velocity of the area in square centimeters that passesunder the dome per second

V _(A) =L×A/T[cm²/s]

The following formula is used to determine the amount of product thatmust be added to 1000 cm³ to achieve the proper dosage delivered by thedevice.

The amount of product to be added to 1000 cm³ is calculated using thefollowing formula:

Product amount=60,000×D×A×L/10000×C×T−60D×A×C

Where

A is the width, L is the length of the application area, T is the timeit takes for the product to travel through the application area, C isthe flow rate of the nozzle and D is the final dose to be applied to thetarget surface in cm³ per m².

To calibrate the equipment, the flow rate is calculated by measuring thevolume per minute delivered by the device. A container such as a beakercan be used to hold and measure the volume of liquid delivered by thenozzle within a given time.

Step 1

How many seconds it takes for 1 [m²] to pass under the dome must bedetermined

If A×L/T[cm²/s]—1[s]

10,000 [cm²]—X[s]

X=10⁴ [cm²]×[s]×T/A×L[cm²]=10⁴ T[s]/A×L

Therefore, 1 [m²] passes under the dome in 10⁴ T [s]/A×L

Step 2

How many [cm³] of the mixture are applied to 1 [m²] must be determined

Let C=flow rate of the nozzle per minute

Therefore, q=C/60=flow rate of the nozzle per second.

The volume of mix that is applied to 1 [m²] is:

C/60 [cm³/s]×10⁴ T[s]/A×L=10⁴ T×C/60A×L[cm³]

D being the dose of product to apply per [m²], it can be establishedthat:

the water per[m²] is (10⁴ T×C/60 A×L)−D

The product per [m²]=D

Therefore, the rule of three to obtain the dosage in 1000 [cm³] of wateris:

[10⁴ T×C/60 A×L−D]—D

1000—X

where X=1000 D/[(10⁴ T×C−D60 A×L)/60 A×L]

X=60.000 D×A×L/[10⁴ T×C−D60×A×L][cm³]

where X are the [cm³] of product that must be added to 1000 [cm³] ofwater in order to deposit D [cm³] of product per treated [m²] ofconveying line.

In some embodiments, the invention also relates to an electrostaticapplication method because it comprises the steps of:

-   -   providing an air flow to an insulating hood (9) of an        electrostatic emission antenna (7) and to an air-liquid nozzle        (6) that is separated from the electrostatic emission antenna        (7).    -   providing a liquid flow from a tank (5) to the air-liquid nozzle        (6) by means of a positive displacement pump (4);    -   regulating the air flow by means of a pressure regulator (12)        and an air flow regulator (13);    -   regulating the liquid flow (35) that passes through a set of        restrictors (26); and    -   turning on the power going to the electrostatic emission antenna        (7).

wherein the method further comprises connecting the power of atemperature control system which includes connecting the power of anozzle heater (11) and the power of a tank heater.

In some embodiments, the electrostatic application method comprisespowering a nozzle heater (11) which is supported by a heater cover (47);wherein the heater cover (47) is made of heat conducting material,wherein the nozzle heater (11) and the heater cover (47) are tightlyconnected, the latter being in turn tightly fitted to a flat surface ofthe nozzle so that the nozzle heater (11) can heat the nozzle bycontact.

Wherein the step of providing a dry air flow going to the insulatinghood (9) of an electrostatic emission antenna (7) of the electrostaticapplication method, according to some embodiments, comprises forming anair jet between an external tube (53) and an internal tube (52) of thehood (9), which dries the area formed around the central space throughwhich the high-voltage conductive element (56), that goes to theelectrostatic emission antenna (7), exits; the air jet prevents thesurface around the space where the high voltage conductive element (56)exits from getting wet and prevents the formation of an electric arcthat can produce an electric spark or a flame that can nullify theeffect of the electrostatic field on the device. Wherein the step ofproviding a dry air flow going to the insulating hood (9) of anelectrostatic emission antenna (7) comprises forming an air jet betweenan external tube (53) and an internal tube (52) of the hood (9), whichdries the area formed around the central space through which thehigh-voltage conductive element (56), that goes to the electrostaticemission antenna (7), exits; the air jet prevents the surface around thespace where the high voltage conductive element (56) exits to get wetand prevents the formation of an electric arc that could produce anelectrical spark or a flame that could nullify the effect of theelectrostatic field on the device.

Wherein the step of regulating the liquid flow that goes to the nozzle(6) of the electrostatic application method, according to someembodiments, is carried out by means of a binary switch system (40) thatincludes solenoid valves (41) that regulate the amount of liquid thatpasses through a set of restrictors (26); that includes opening orclosing the solenoid valves (41) to regulate the amount of liquid thatpasses through restrictors (31, 32, 33, 34) that have different internaldiameters ranging from approximately 0.3 mm to 1 mm.

Wherein the step of regulating the flow of a return line (24) of theelectrostatic application method is carried out by means of a regulatingvalve (36), a flow control (37) and a flowmeter (38) that measures theliquid flow that is returned to the tank (5), according to someembodiments; wherein the liquid flow in the return liquid line (24) isgreater, by approximately 2 liters per minute, which allows toaccurately measure the amount of return liquid and at the same timeallows to stir the contents of the tank with the liquid that returns tothe tank.

Wherein the step of regulating the air flow of the electrostaticapplication method is carried out by means of a pressure regulator (12)and an air flow regulator (13), wherein the air flow regulator (13)comprises a flowmeter provided with a steel ball in a graduated column,wherein the steel ball is pushed by the flow of compressed air that issupplied by a compressor (15), according to some embodiments; whereindry air exits from the compressor through an air line (16) that branchesinto two air lines: a first air line (17) that carries air to thenozzle, and a second air line (18) that carries air to the insulatinghood (9) of the electrostatic emission antenna (7).

Wherein the step of regulating the air flow of the electrostaticapplication method, comprises regulating the pressure of the first airline (17) that carries air to the nozzle by means of a pressureregulator (12) and an air flow regulator (13) on the control console(2), according to some embodiments; wherein regulating the air flowallows to regulate the droplet size coming out of the nozzle, where thedroplet size is inversely proportional to the applied air flow.

Examples of Application on Blueberries

In general, antifungal products to treat the fruit are not appliedpost-harvest, especially in blueberries because when applying theantifungal products, water is added to the fruit, and wetting the fruitbefore packing is a problem.

In some embodiments, the device allows this problem to be overcome bythe application of post-harvest antifungal products, especially inblueberries, because the device prevents wetting the fruit beforepackaging. In some embodiments, electrostatic device allows a dry effectapplication that has the advantage of not altering the characteristicsof the fruit cuticle, such as the bloom, a natural wax that covers thefruit and does not wet it, thus avoiding a drying step afterapplication.

Application of 1 cm³/cubic meter to 10 kilos of blueberries. Workingfrom 0 to 5° C. evaporates less and requires greater control of thedroplet size given that the evaporation of the product is minimal on thesurface of the blueberries at temperatures between −5° C. to 5° C.

For example, a product to be applied to blueberries can be Nature Coverby DECCO.

By controlling the droplet size, a product drying step is avoided. Usinga smaller droplet size results in the surface of the fruit being lesswet and the packing line being less contaminated.

The electrostatic device is installed in the pre-calibrator area of theblueberries. The height of the main commune must be adjusted through theclamp (69) and the length regulator of the nozzle holder (66) must alsobe adjusted so that it is at an average distance in the width of theconveyor line, so that the application system is at a suitable heightand position in the application area.

Example of Application on Cherries

In the post-harvest treatment, the cherries are carried in water toavoid damage to the fruit and to avoid pitting. The transport water ofthe cherries contains a fungicide. After use, the water and thefungicide are eliminated causing contamination and economic losses.

In some embodiments, the device replaces the fungicide used in thecherry transport water by an electrostatic application of post-harvestfungicide product at the exit of each of the production lines.

In some embodiments, applying a fungicide to cherries with the equipmentavoids applying large amounts of fungicide in the water that transportsthe cherries, and therefore avoids economic losses and the contaminationthat occurs when eliminating the water mixed with fungicide that is usedin the process chain.

In one embodiment of the device for application on cherries, theequipment is of the portable type. The application on cherries ismicronized, the required droplet size is smaller. 15,000 volts are usedand the temperature must be controlled.

In some embodiments, the electrostatic device may be refitted for theapplication on cherries in that it is separated into, on the one hand,the stand comprising the pump, tank and the control console and, on theother hand, the nozzle and the electrostatic generator system that canbe installed in the dome, so that one equipment can be installed foreach cherry packing line.

The device for applying a fungicide product to cherries can be locatedin the fruit drop area to achieve a radial application of the fungicideproduct, covering the entire surface of the fruit. Application in thedrop area is carried out on cherries and nuts.

Moreover, given that the green petiole must be maintained in cherries,silicon or edible toppings (for example, cinnamon, propolis) are appliedthereon. In addition, a fungicide product (such as Scholar® or PROBION®)may be applied.

Application on plums, where wetting is carried out at a rate of 8cm3/meter2, is another example of application. When working in packingareas at room temperature, for example from 10 to 25° C., evaporation isgreater and it is easier and faster to obtain dry fruit afterapplication.

Another example of application that can be mentioned is that ofScholar's fungicide in addition to wax on apples.

Examples of Treatment Agent or Products.

The treatment agent or products are selected from chemicals, organicproducts, waxes or gases, among which are products that have propertiesas phytosanitary agents, fungicides, anti-dehydrants and disinfectants.For example, a chemical agent with protective activity intended toprolong the preservation of fruits or vegetables. The chemical agentcomprises, for example, a liquid or gas, with an antioxidant effect, adisinfecting agent, an insecticide, a germicide or a fungicidal effect.

An organic agent comprises, for example, a citric extract, propolis,synthetic waxes or sugars. Wax or a sugar coating, for example, can playan important role to avoid moisture loss, prevent dehydration of thefruit or vegetable, maintain its organoleptic characteristics andmaintain a constant weight of the fruit or vegetable during the periodof storage and transport. Sugars, for example, can be a preparationobtained from the very fruit to be treated.

Fungicidal compounds such as Fluodioxynil, Fenhexamid, Iprodione andcompounds like potassium bicarbonate can also be applied. Scholar® is abroad-spectrum contact fungicide, used for the treatment of stonefruits, pome fruits, citrus, pomegranates and blueberries inpost-harvest, before packaging, to control pathogenic fungi that causediseases or rot that affect the fruit, during storage and/or transportto destination markets.

According to some embodiments, the products can be applied post-harvestwith the device, for example, to fruits and also to vegetables such aspotatoes, Brussels sprouts, avocados, etc.

A biological agent applied by the device can be, for example, bacteria.For example, Bacillus subtilis produces spores and metabolites, and maybe pretreated to produce spores. This Bacillus may be applied incombination with Scholar, Scholar being a fungicide that is harmless toBacillus subtilis, so both can be applied in a mixture.

Bacillus subtilis is also used for application on grapes. The appliedBacillus subtilis is generally previously treated to produce spores. TheBacillus thus treated is used both for its ability to produce spores andfor its ability to produce metabolites.

A special strain of Bacillus that is resistant to UV light and anaerobicmay be used.

Bacillus is competing against fungi. That is to say, when the necessaryconditions for the growth of fungi are present, there are also thenecessary conditions for the Bacillus spores to become bacteria thatcompete for space and prevent the reproduction of pathogenic fungi forthe fruit.

The Bacinpost product includes Bacillus plus exudate that has afungicidal contact effect. Bacinpost is a highly recommended preventivebiocontroller for the control of gray rot in table grape, blueberry andtomato crops. Bacinpost comprises a concentrated suspension ofvegetative cells, endospores and active secondary metabolites. Thenative strain of Bacillus subtilis C110 quickly colonizes micro-woundsin the plant thanks to its excellent biological characteristics whichallow it to adapt to local environmental conditions and competeeffectively for space and nutrients with Botrytis cinerea, a fungus thatcauses gray rot.

In general, Bacifrut is applied in orchards. The Bacinpost product hasmore secondary metabolites than Bacifrut. For example, Scholar(Fludioxonil) has fungicidal activity by contact and is available as anemulsifiable concentrate for post-harvest application in the treatmentof fungal diseases caused by fungi such as Botrytis (Botrytis cinerea),which attack collected fruits such as cherries, plums and peaches,citrus fruits, apples and pears. The product is applied directly on thefruit by means of a shower (“Drencher” system) or immersion for 30-60seconds before the fruit enters the chamber. Approximately 4.5 L ofsolution/ton of fruit is applied.

The electrostatic device, on the other hand, allows reducing the amountof product applied, using 9 ml of product/ton of fruit, for example,which represents a significant economic advantage.

Serenade® is a biological fungicide that can be used in general againstfoliar and soil diseases in fruit trees and vegetables. Based on sporesof the beneficial QST 713 strain of Bacillus subtilis bacteria.Serenade® is a fungicide that provides control with high levels ofenvironmental safety, human safety, and safety to non-target organisms,including bees when used as directed. It can be used when other cropprotection tools cannot, due to its short pre-harvest interval and theabsence of residues. It helps producers meet re-entry intervals, manageworker safety requirements, and meet food chain specifications. It isexempt from the maximum residue limit, is harmless to bees and iscompatible in mixture with other phytosanitary and nutritional products.

Copper

Copper can be used for organic agriculture as a fungicide or bactericidethanks to its disinfecting action (it eliminates microorganisms), sinceit prevents and cures the development of a certain group of fungi thatattack plants. One of the main uses of copper oxychloride is itsfungicidal activity. Copper oxychloride is a natural product that has apreventive action. Its field of action is quite large as it can be usedagainst a large number of fungi and in different types of crops and itis quite persistent in the plant.

The action stage of copper begins with the germination of fungal spores;hence its action is limited to prevent the appearance of fungaldiseases. Its mode of action is simple: various fungi in their initialstages are unable to grow or reproduce when the Cu content is above acertain level (2 or 3 ppm, for example).

As an example, copper sulfate pentahydrate can be applied with theelectrostatic device, according to some embodiments. However, coppersulfate pentahydrate cannot be added in mixture with bacilli due to thebactericidal effect of copper.

Ozone Application Example

In one embodiment, the device is used to apply ozone to replace the airdirected to the nozzle with ozone and apply a mixture of ozone andwater. Ozone is considered a better disinfecting compound than chlorine,with the advantage that it leaves no residue since ozone transforms intooxygen in a few minutes.

Cleaning companies using ozone have emerged due to the increasinglymarked innovation in methods for disinfecting and cleaning industries,public establishments, such as schools and hospitals, and even homes.Ozone is a useful tool for disinfecting and cleaning, due to itsbactericidal and bacteriostatic effect.

The application of ozone has been used for water treatment since theturn of the century. Today, its use for this purpose extends to thetreatment of all kinds of environments, and even the human body.

For ozone application, the device requires an ozone generator as anadditional device. The ozone generator is installed in the air linedirected to the nozzle and ozone mixed with water is applied. Forexample, a 20 G generator is used that allows a cold room to besanitized in 20 minutes, applying 20 liters per minute of a mixture ofozone and water.

Ozone oxidizes the proteins of the virus envelope and modifies theirstructure, preventing them from anchoring in the host cells, an actionthat prevents them from reproducing and consequently causes their death.Ozone fights pathogens by oxidative action that causes irreversibledamage to fungal cells, eliminating them from all kinds of environments.Ozone is enriched oxygen that comprises three oxygen atoms, is unstable,and breaks down relatively easily into oxygen. Due to thischaracteristic, ozone is highly efficient as a disinfectant and is themost serious competitor of chlorine.

Ozone is a slightly blue gas with a characteristic odor that can beperceived after thunderstorms. It is poorly soluble in water and veryvolatile. It stays in the water only a few minutes; in its application,approximately 10% is lost due to volatilization. The doses necessary todisinfect water vary according to the water quality.

Ozone is considered the most efficient microbicidal disinfectant andrequires fairly short contact times. The speed with which ozone killsbacteria is considerably greater than that of chlorine, about threethousand times greater, because, although both are oxidants, themechanism of action is different. Ozone kills the bacteria by disruptingthe cell diaphragm. Instead, chlorine must enter the bacterial cell walland diffuse into the cytoplasm, an action that is highly dependent oncontact time.

Technical Characteristics of the Equipment, According to SomeEmbodiments

The equipment allows working at a voltage: 110-220 volts, a frequency:50-60 Hz, an air flow rate: 30 liters per min, air pressure: 1-2atmospheres (15-30 psi)

In some embodiments, the equipment allows the application ofnon-viscous, non-corrosive products, air, ozone, agricultural products,organic products, and conductive products.

The equipment works at an electrostatic voltage of between 5,000 to40,000 volts, preferably between 15,000 to 30,000 volts, more preferablyat a voltage of 25,000 volts. The pump works at a flow rate of 1 to 400cm3 per minute.

Equipment Operation Mode

To start the equipment, the following condition should be met:

all switches must be in the off position and the regulating valves mustbe closed.

To start the equipment, follow the steps listed below:

-   -   Connect the equipment to the power outlet    -   Connect the equipment to the air intake    -   Turn on the equipment (using switch on console)    -   Place the switch in “Manual Control”    -   Start the pump (using switch on console)    -   Adjust the liquid valve until the desired flow rate is set    -   Adjust the air valve until the desired atomization rate is set    -   Turn the electrostatic power on (using switch on console)

To end the application, follow the steps listed below:

-   -   Turn off the electrostatic power    -   Turn off the pump    -   Turn off the computer    -   Turn off the air supply

By following these steps at the end of the application, theconfiguration of the air and liquid regulating valves is maintained, sothat when restarting the operation of the equipment, it is alreadycalibrated.

To restart the application, follow the steps listed below:

-   -   Turn on the equipment.    -   Start the air supply.    -   Start the pump    -   Turn the electrostatic power on

REFERENCES

-   -   1 Electrostatic device schematic    -   2 Control console    -   3 Remote control    -   4 Pump    -   5 Tank    -   6 Nozzle    -   7 Electrostatic emission antenna    -   8 High voltage power line    -   9 Hood    -   10 Heater power line    -   11 Nozzle heater    -   12 Pressure regulator    -   13 Air flow regulator    -   14 Additional pressure regulator    -   15 Compressor    -   16 Main air line    -   17 First air line    -   18 Second air line    -   19 Second air line restrictor    -   20 Key    -   21 Fork    -   22 First liquid line    -   23 Second liquid line    -   24 Liquid return line    -   25 Line filter    -   26 Set of restrictors    -   27 First check valve    -   28 Second check valve    -   29 Filter    -   30 Third liquid line    -   31 1 XF Restrictor    -   32 2 XF Restrictor    -   33 4 XF Restrictor    -   34 8 XF Restrictor    -   35 Liquid flow regulating system    -   36 Regulating valve    -   37 Flow control    -   38 Flowmeter    -   39 Tank heater    -   40 Binary switch system    -   41 Solenoid valve    -   42 Nozzle holding tube    -   43 Nozzle holder    -   44 Nozzle cap    -   45 Bolts    -   46 Anchor plate    -   47 Heater cover    -   48 Power line hole    -   49 Liquid inlet    -   50 Air inlet    -   51 Ground cable    -   52 Internal tube    -   53 External tube    -   54 Top hole    -   55 Bottom side hole    -   56 High-voltage conductor element tube    -   57 Dry air    -   58 Outer surface of the inner tube    -   59 Upper tube    -   60 Middle part of the hood    -   61 Bottom hole    -   62 Inner wall    -   63 Outer wall    -   64 Air chamber    -   65 Stand    -   66 Nozzle holder length adjuster    -   67 Main column    -   68 Fixation    -   69 Clamp    -   70 Folding clamping element    -   71 Anchorage    -   72 Anchor hole    -   73 Recess    -   74 Slit    -   75 Flat surface    -   76 Holding flap

1. An electrostatic device comprising: an air flow regulator systemcomprising a pressure regulator and an air flow regulator; a liquid flowregulating system comprising a set of restrictors; an electrostaticsystem comprising an electrostatic emission antenna and an insulatinghood of the electrostatic emission antenna; an air-liquid nozzle that isseparated from the electrostatic emission antenna; a tank; and apositive displacement pump.
 2. The device of claim 1, comprising atemperature control system comprising a nozzle heater and a tank heater.3. The device of claim 1, wherein the liquid flow regulating systemcomprises an in-line set of restrictors, a binary switch system, aregulating valve, a flow control, and a flowmeter.
 4. The device ofclaim 3, wherein the liquid flow regulating system comprises a firstline of liquid coming out of the tank, driven by the pump up to a forkwhere it separates into: a second liquid line and a return liquid line;wherein the second liquid line comprises a set of restrictors and abinary switch system equipped with solenoid valves that regulate theamount of liquid that goes to the nozzle, and wherein the regulatingvalve, the flow control and the flowmeter that measures the liquid flowthat is returned to the tank are located in the return liquid line. 5.The device of claim 4, wherein the second liquid line, after passingthrough the set of restrictors, comprises a first check valve thatprevents the liquid from returning to the restrictors so that the liquidflow directed to the nozzle through a third liquid line is kept measuredand constant.
 6. The device of claim 3, wherein the set of restrictorscomprises restrictors having different internal diameters ranging fromapproximately 0.3 mm to 1 mm.
 7. The device of claim 1, wherein theelectrostatic system, a protective and insulating hood, a tube for ahigh-voltage conductive element that carries a high voltage power lineand supports that secure the high-voltage conductive element tube to ahorizontal part of a nozzle holding tube, wherein the electrostaticemission antenna is located at the bottom of the hood that isolates theelectrostatic emission antenna from the rest of the components of thedevice.
 8. The of claim 1, wherein the hood comprises an internal tubeand an external tube, an upper hole for the entry of a high-voltageconductive element that exits through a lower hole of the internal tube,and a lower lateral hole for entry of dry air that acts as an insulator.9. The device of claim 1, wherein the hood comprises a lower lateralhole through which a hose that injects dry air in the form of an air jetenters between an external tube and an internal tube, wherein the airjet dries the area formed around the central space through which ahigh-voltage conductive element, that goes to the electrostatic emissionantenna, exits; the air prevents the surface around the space where ahigh-voltage conductive element exits from getting wet and preventsformation of an electric arc that can produce an electric spark or aflame that can nullify the effect of the electrostatic field on thedevice.
 10. The device of claim 1, wherein the nozzle comprises a liquidinlet that receives the liquid coming from a third liquid line and anair inlet that it receives the air that comes from a first air line;wherein the nozzle is housed in the space formed between a nozzlesupport holder and a flat surface of the lower end of a holding tube;wherein the nozzle holder forms a rectangular frame with an open end,the open end comprises fastening tabs having threaded holes into whichbolts are screwed to secure a nozzle cap; wherein the nozzle cap has aflat shape and has two perpendicular surfaces that comprise a recessdesigned to be inserted into an anchor slit located at a rear of a lowerend of a nozzle holding tube.
 11. The device of claim 10, wherein thenozzle holder houses a nozzle heater which is supported by a heatercover; wherein the heater cover is made of heat conductive material, hasa flat shape and two perpendicular surfaces that comprise an anchoringprotrusion; the anchoring protrusion is inserted into an anchor hole ofthe nozzle holder to hold the nozzle heater in place.
 12. The device ofclaim 10, wherein the rectangular frame of the nozzle holder is closedby an anchor plate by bolts that are inserted into holes located at theends of the anchor plate; wherein the holes of the anchor plate fit withthe threaded holes located in the fastening tabs of the nozzle holder;wherein the bolts pass through the holes in the anchor plate and pushthe nozzle cap into the slit to hold the nozzle and heater in place. 13.The device of claim 1, wherein the device comprises a compressor thatprovides dry air through an air line that branches into two air lines: afirst air line that carries air to the nozzle, and a second air linethat carries air to the insulating hood of the electrostatic emissionantenna, and wherein the second air line that carries air to theinsulating hood comprises a restrictor that controls the amount of airgoing to the insulating hood.
 14. The device of claim 13, wherein thefirst air line that carries air to the nozzle passes through a controlconsole where it encounters the flow regulating system comprising apressure regulator and an air flow regulator, which allows regulatingthe air flow going to the nozzle; wherein the air flow regulatorcomprises a flowmeter that comprises a small steel ball in a graduatedcolumn, where the steel ball is pushed by the flow of compressed airsupplied by the compressor.
 15. The device of claim 1, wherein the tankis made of stainless steel or PVC, has a 5 to 60 liters capacity, andcomprises a stirring system including three pumps arranged in a tankbase; the tank also includes a temperature control system that allowsthe product to be kept at a suitable temperature to prevent the liquidfrom freezing in hoses when the ambient temperature is below 0° C. 16.An electrostatic application method comprising: providing an air flow toan insulating hood of an electrostatic emission antenna and to anair-liquid nozzle that is separate from the electrostatic emissionantenna; providing a liquid flow from a tank to the air-liquid nozzle bya positive displacement pump; regulating the air flow by a pressureregulator and an air flow regulator; regulating the liquid flow thatpasses through a set of restrictors; and turning power on that goes tothe electrostatic emission antenna.
 17. The electrostatic applicationmethod of claim 16, it further comprising connecting power of atemperature control system that comprises connecting power of a nozzleheater and connecting power of a tank heater.
 18. The electrostaticapplication method of claim 16, comprising powering a nozzle heaterwhich is supported by a heater cover; wherein the heater cover is madeof heat conducting material; wherein the nozzle heater and the heatercover are tightly fitted and are, in turn, tightly secured to a flatsurface of the nozzle so that the nozzle heater can heat the nozzle bycontact.
 19. The electrostatic application method of claim 16,comprising regulating the liquid flow going to the nozzle by a binaryswitch system comprising solenoid valves that regulate an amount ofliquid that passes through a set of restrictors; comprising opening orclosing the solenoid valves to regulate the amount of liquid that passesthrough the restrictors that have different internal diameters rangingfrom approximately 0.3 mm to 1 mm.
 20. The electrostatic applicationmethod of claim 16, comprising regulating flow of a return line by aregulating valve, a flow control and a flowmeter that measures theliquid flow that is returned to the tank; wherein the liquid flow in thereturn liquid line is greater, approximately 2 liters per minute, whichallows to accurately measure the amount of return liquid and at the sametime allows to stir the contents of the tank with the liquid that returnto the tank.
 21. The electrostatic application method of claim 16,comprising providing a dry air flow going to the insulating hood of theelectrostatic emission antenna, which comprises forming an air jetbetween an external tube and an internal tube of the hood, that driesthe area formed around the central space through which a high-voltageconductive element, that goes to the electrostatic emission antenna,exits; the air jet prevents a surface around the space where the highvoltage conductive element exits from getting wet and prevents formationof an electric arc that can produce an electric spark or a flame thatcan nullify the effect of the electrostatic field of the electrostaticapplication method.
 22. The electrostatic application method of claim16, wherein the air flow regulator comprises a flowmeter provided with asmall steel ball in a graduated column, where the steel ball is pushedby the flow of compressed air that is supplied by a compressor; whereindry air exits from the compressor through an air line that branches intotwo air lines: a first air line that carries air to the nozzle, and asecond air line that carries air to the insulating hood of theelectrostatic emission antenna.
 23. The electrostatic application methodof claim 22, comprising regulating pressure of the first air line thatcarries air to the nozzle by the pressure regulator and the air flowregulator on a control console; wherein regulating the air flow allowsto regulate the droplet size coming out of the nozzle, where the dropletsize is inversely proportional to the applied air flow.